Hospital acquired pneumonia &

Ventilator associated pneumoniaDiagnosis and management

David Walker

Consultant in Critical Care MedicineUniversity College London Hospitals

HealthcareAssociatedPneumonia

(HCAP)

Community Acquired

Pneumonia<48 hours after admission

(CAP)

Hospital Acquired

Pneumonia>48 hours after admission

(HAP)

Defining the illness

Ventilator associated pneumonia

>48 hrs after intubation(VAP)

EpidemiologyPneumonia the leading cause of hospital acquired infection

• 0.5 – 1% of all hospital admissions

• Mortality 10 – 30% (MDR – 70%)

• Most deaths outside ICU

• Huge health resource implications

• Post surgery pneumonia – 20% mortality

Ventilator associated?• Intubation associated pneumonia

• Endotracheal tube associated pneumonia

• 10 international guidelines in 7 years (50% expert opinion)

• 45% healthy volunteers microaspirateduring sleep

• Rate may double in critically ill

• 75% of patients critically ill -oropharynx colonised within 48 hours

• Mechanical barrier

• Humoral and cellular response

The fate of hospitalised patients?

HAP, HCAP & VAPRisk factors

• Age >70

• Low GCS

• PPI/H2 Blockers

• Chronic illness

• Chronic lung disease

• Aspiration

• Chest surgery

• Antibiotics

• Seasonal

• Frequent vent circuit changes

Diagnosis of HAP, HCAP & VAP(ATS/IDSA 2005)

The clinician should suspect infection :-

• Fever*

• Leukocytosis*

• Purulent sputum*

• Decline in oxygenation

In the presence of a progressive lung infiltrate on CXR with two of signs*

Gives best clinical prediction BUT, lack specificity

DANGER: Over treatment of infection

HAP/VAP - UCLH clinical approach

White cell count

Fever

CRP

Appropriate

CXR

Hourly ventilator

settings check

Increasing resp rate

Decreasing tidal volume

Increasing ventilation

Declining P/F ratio[

+

A randomised trial of diagnostic techniques for VAP(The Canadian Critical Care Trials group) n=740

BAL + Quantitative V Endotracheal aspiration + non – quantitative

* No difference in primary endpoint – 28 day mortality*

• Similar rates of overall antibiotic use

• Similar days alive without antibiotics

• Similar length of ICU stay

• Similar organ dysfunction score

2006;355:2619-30

Guideline for early, appropriate antibiotics

• `Inappropriate antibiotics cost lives`

• `Delays in initial therapy costs lives`

• `Physicians deviating from ATS guidelines for HCAP therapy resulted in increased mortality`

• `Prescribing policy based on resistance patterns locally improves outcome`

• `Single agent, unless guided by high risk of MDR factors`

Kollef M. Chest. 2006

Zilberg. Chest. 2008

Beardsley Chest. 2006

Aarts M. Crit Care Med. 2008

Iregui. Chest. 2002

Infection suspected

Obtain sample (Non-BAL /semi quantitative )

Empiric therapy – with local guidance

48 - 72 hours assess clinically and micro

Yes

Cult neg Cult pos Cult neg Cult pos

Considerdiagnosis

Considerantibioticsdiagnosis

StopAntibiotics?

De-escalate(5-7 days)

Noimprovement

VAP is deadly and expensive

Variable No VAP (n=692) VAP (n=127) p value

Sepsis n(%) 75 (11) 43 (44) <.001

ICU LOS 4 days 26 days <.001

Hospital LOS 13 days 38 days <.001

Death n (%) 237 (34) 64 (50) <.001

Total cost $21,620 $70,568 <.001

# ICD-9 codes 9 10 <.001

Warren et al Crit Care Med 2003 31:1312-17

Give your patients a FAST HUG (at least) once a day

• Feeding

• Analgesia

• Sedation

• Thrombo-prophylaxis

• Head of bed elevation

• Stress ulcer prophylaxis

• Glucose control

Vincent JL. 2005;33:1225-1229

Feeding

Feeding protocols

NG tube protocols

GI protection protocols

Patientpositioning

Head up (Semi-recumbent positioning)

• Defined as elevating the head of the bed at least 300

• One randomised, prospective trial:

• 86 patients positioned semi-recumbent (30°) or supine

• Frequency of VAP assessed (clinical and quantitative BAL) 20% V 38% VAP

Drakulovic et al, Lancet 1999 354(9193):1851-58

Ulcer prophylaxisRCT, comparing 3 strategies H2 antag, Mg hydrox & Sucralfate

Sucralfate reduced late pneumonia (5% v 16% v 21%)

• Lower gastric pH

• Lower gastric colonisation

• Non-significant trend to bleeding (Prod`hom. Ann Int Med 1994)

Large cohort study PPI v H2 antag (>3 days hospitalised)

PPI associated with significantly more HAP (not H2 antag)

Where possible we avoid these drugs in those NOT at considerable risk of GI haemorrhage and use H2 > PPi > antacids

Herzig. JAMA. 2009

Analgesia & Sedation

Score Comment

3 Agitated, restless

2 Awake, uncomfortable

1 Aware, but calm

0 Roused by voice

-1 Roused by movement

-2 Roused by noxious stimulus

-3 Unrousable

Rapid shallow breathing index = f/TV (BPM/L) where <105 predictive of extubation

UCLHSedation score

Thromboprophylaxis

LMWH

Early mobilisation

Mechanical compression devices

Anti embolic stockings

Development of VAP

Rello and Diaz Crit Care Med 2003 31(10):2544-51

Days of intubation

Odds ratio

Therapist-Driven Weaning Protocols(MDT approach to weaning)

• RCT of 300 patients

• Physician order versus RN- and RT- driven weaning trials

• Duration of mechanical ventilation and cost were both lower

• Less complications in intervention group

Ely et al. NEJM 1996 335:1864-69

Sterile gowns

Plastic aprons Latex free gloves

Infection Control – Care bundles

Selective decontamination of the digestive tract(antiseptic mouth wash, non-absorbable antibiotics, systemic antibiotics)

Oropharynx:

2007 metaanalysis 11 trials, 3242 patients

Oral antibiotics / antiseptic / placebo / standard mouth care

VAP reduced by oral mouthwash only

Chlorhexidine 0.12% 15mls/bd

Neither affected outcome

Less VAP, same mortality same length of ventilation

Safe, cheap and easy to apply

Digestive tract(Against aerobic bacilli and Candida spp Maintaining anaerobic flora)

5939 patients RCT

Cefotaxime iv, Colistin, Tobramycin, Amphotericin B

Control group death rate 27.5%Death rate reduction at 28 days

3.5% gut decontamination2.9% oropharyngeal decontamination

De Smet et al. NEJM 2009. 1;360(1):20-31

UCLH approach (and UK)

Better studies report small improvements Implication for medicalpatients is small

C-Difficile, Gram +ve/-ve organisms real concern

Concerns for resistance not upheld in literature

British Society of Antimicrobial Chemotherapy support

National Institute of Clinical Excellence

• More UK based research

• Specialist Advisor concerns

Aspiration past the cuff: (basic steps for prevention)

• Semi-recumbent positioning

• Avoid gastric over-distention

• Avoid unnecessary sedation

• Discontinue nasogastric tube

• Positive end expiratory pressure

AspirationGross aspiration or

microaspiration around

endotracheal tube cuff

Continuous Aspiration of Subglottic Secretions (CASS)

• Secretions above ETT cuff may increase risk of aspiration

• Removal decreases the pressure gradient that promotes

leakage and the volume that can leak

• Special endotracheal tube with a separate suction lumen

• Suctioning of secretions can be continuous or intermittent

Subglottic secretion drainage with integrated suction line

Continuous aspiration of Subglottic secretions (CASS)

5 studies, 896 patients intubated

• Continuous aspiration

• Halved incidence VAP

• Reduced length of ICU stay

• Reduced antibiotic use

Dezfulian. Am J Med. 2005

Efficacy of Subglottic Suctioning

Cuff Technology

• Current cuffs are not 100%

occlusive

• Folds in wall create channels that

allow fluid leakage

• Folding is related to cuff shape and

material

Experiments with cuff profile

• Taper shaped cuff

• Cuff material is

minimized

• Limited pathway

for aspiration

Lorente et al. AJRCCM Vol 176 pp 1079 – 1081, 2007

UCLH approach to VAP Prevention (Teamwork)

Nurse

Doctor Physio

Patients